The Inscribed Angle Theorem

1.) Move the points on the circle. What do you observe?
2.) Explain why your observation will always be true for all angles.

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Theorem: If an inscribed angle and a central angle has the same intercepted arc, then the measure of the inscribed angle is half that of the measure of the central angle.

I have written a detailed proof of the Inscribed Angle Theorem in Mathematics and Multimedia.